Creating the Model
Create the model in CADFEKO. Define any ports and sources required for the model. Specify the operating frequency or frequency range for the model.
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Define the following variables.
- freq = 1e9 (The operating frequency.)
- fmin = 0.4e9 (The minimum frequency.)
- fmax = 1.5e9 (The maximum frequency.)
- lambda = c0/freq (The frequency for free space wavelength.)
- L0 = 0.2375 (Length of the reflector element in wavelengths.)
- L1 = 0.2265 (Length of the driver element in wavelengths.)
- L2 = 0.223 (Length of the first director element in wavelengths.)
- L3 = 0.223 (Width of the second director element in wavelengths.)
- S0 = 0.3 (Spacing between the reflector and driver element in wavelengths.)
- S1 = 0.3 (Spacing between the driver element and first director element.)
- S2 = 0.3 (Spacing between directors.)
- r = 0.1e-3 (Wire radius in mm.)
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Create the dipole (driven element) of the Yagi-Uda antenna.
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Create a line.
- Start point: (0, 0, -L1*lambda)
- End point: (0, 0, L1*lambda)
- Add a wire port (vertex) to the middle of the line.
- Add a voltage source to the port. (1 V, 0°, 50 Ω).
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Create a line.
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Create the reflector of the Yagi-Uda antenna.
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Create a line.
- Start point: (-S0*lambda, 0, -L0*lambda)
- End point: (-S0*lambda, 0, L0*lambda)
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Create a line.
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Create the first director of the Yagi-Uda antenna.
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Create a line.
- Start point: (S1*lambda, 0, -L2*lambda)
- End point: (S1*lambda, 0, L2 *lambda)
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Create a line.
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Create the second director of the Yagi-Uda antenna.
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Create a line.
- Start point: ((S1+S2)*lambda, 0, -L3*lambda)
- End point: ((S1 + S2)*lambda, 0, L3*lambda)
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Create a line.
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Set the incident power as follows:
- Select Incident power (transmission line model).
- Source power (Watt): 25
- Real part of Z0: 50
- Set the continuous frequency range from fmin to fmax.
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Specify the symmetry about 2 principal planes.
- Y=0: Magnetic symmetry
- Z=0: Electric symmetry
Tip: Exploit model symmetries (if it exists) in a large or complex model to reduce computational costs.